Dental matrix



Dec. 29, 1953 J. WALSER 2,663,935

DENTAL MATRIX Filed Feb. 3, 1951 IN V EN TOR.

Patented Dec. 29, 1953 UNITED STATES PATENT OFFICE DENTAL MATRIX Julius Walser, Radolfzell, Bodensee, Germany Application February 3, 1951,'Seria1 No. 209,233

2 Claims. (CI. 32-163) This invention relates to a dental matrix.

The object of the invention is to provide .a double-band matrix which is suitable ior enclosing cavities in front teeth a most simple and fully automatic manner. The invention will now be described with reference to the accompanying drawings, Figs. 1 to 5. In these drawings,

Fig. 1 is a plan view of one of the bands;

Fig. 2 is a top plan view of the matrix;

Fig. 3 is a rear view thereof;

Fig. 4 is a front view thereof; and

Fig. 5 is a bottom-plan view of a stressing means for tightly applying certain matrix partsagainst the tooth periphery when the matrix has been positioned in the gap between adjacent front teeth. For the sake of clearness that stressing means has been omitted in Figs. 2 to e but-it will be fully .apparent from the following description how the stressing means is to be connected to the other parts of the matrix.

Of the matrix bands, which have superposed side edges, one is designated with A, the other with B. Each of the end edges I Id of both bands has cut into it approximately at the center of the width of the band a longitudinal slot Me, which does not extend to the center of the length of the band. Thus two similarly shaped tongues are formed above and below each slot i ie. Each tongue below a slot He is designated II a, each tongue above a slot l le is designated Mb. The end of each tongue is formed into an eye or tube. In Figs. 2 to 4 the eye below a slot He is designated with Hf and the eye above a slot He with Hg. A wire bail, of steel, is arranged outside of and transversely to the pair of bands at both ends thereof. In the example shown each of said wire bails is formed from a single length of wire. The outside crosspiece Is extends from the central point Ia of each wire bail upwardly into the associated coil, and vertically through said coil, and is bent at it or lu to merge with the top turn of the respective coil. The lowest turn Ix of both coils of each Wire bail is continued by a wire limb ly or la, which extends obliquely toward the associated eye ll of the respective tongue Ha. Both wire limbs of the associated wire bail cross each other and each wire limb ly or I2 is continued by an approximately vertical arm lq, which extends through the associated eye Hf, in which it is held by an offset with which the arm lq extends out of the other end of the eye.

When in the bands A and B the tongues Ha, Hf arranged adjacent to the neck of the teeth are formed as described hereinbeiore, each tongue 1 in may apply itself snugly against the side face of the neck of the front tooth to be treated, which is indicated inFigs. 2 to 4 with dashed lines, without interference by "the tongue lib or eye portion Mg.

Each of .the two eyes My of the palatal tongues 4 12) arranged adjacent to the cutting edge is passed through by the associated wire limb J1 of a U-shaped bail J,.J1; J2, in the direction toward the neck of the .front tooth. An ofiset J2 at the end of the wire limbs J1 holds the bail in position. The-crosspiece J of the bail is preferably straight and will apply itself adjacent to the cutting edge against the wedge-shaped back faces of the adjacent teethshown with dash lines in Figs. 2-4.

To bend each of the matrix bands A and B around one of the tooth side's which delimit the gap between'adjacent teeth and to apply it tightly against the curved front ofthe tooth, tension in the direction of the arrow of Fig. 4 must be applied to the ends of the'labial tongues l lb. These mutually opposite tensile forces may be exercised by a V -s'haped grip of'resilient wire L, Ll-B (Fig. '5). The grip comprises a length of steel wire which at L has a portion of circular configuration, e. g., in the shape or a helix, and further has two jaws forming a neck embraced by a ferrule L3, and divergent .arms L2 terminated by an outwardly open hook L1. The neck portions of the jaws L2 pass through the ferrule L3, which is wide enough to permit of a limited approach of the hooks L1 toward each other by finger pressure applied from the outside on the arms L2.

When finger pressure is thus applied, each hook L1 may be connected to one of the labial tongues llb arranged adjacent to the cutting edge. The means for connecting the hook to the tongue may consist, e. g., of a wire eye K or K1, the inner side portion of which passes through the associated eye Ilg of the tongue Ilb, whereas its outer side portion is seized by the appertaining hook L1 to pull the respective tongue Ilb,outwardly in the direction of the arrows shown in Figs. 2 and 4, as soon as the finger pressure on the spring grip is discontinued.

Iclaim:

1. In a dental matrix comprising a pair of flexible bands having superposed side edges, each of said bands being formed at each end with a longitudinal slot not extending to the center of the length of the band to form two similarly shaped tongues above and below said slot, respectively, said bands being suitable for slidable insertion into a gap between two front teeth with a 3 labial and a palatal tongue of each band arranged adjacent to the neck of said teeth and a labial and a palatal tongue of each band arranged adjacent to the cutting edge of said teeth, the improvement which resides in that each of said labial tongues arranged adjacent to the neck of said teeth and each of said palatal tongues is formed in its end with an eye, and each of said labial tongues arranged adjacent to the cutting edge is provided at its end with means for connection to a wire part suitable to pull said labial tongues arranged adjacent to said cutting edge apart from each other, and that said bands are connected by two resilient wire bails which extend transversely to said tongue ends arranged adjacent to the neck of said teeth, One of said bails extending labially, the other palatally of said bands, each of said wire bails comprising a wire coil associated with each of said bands, a wire limb branching obliquely from each of said wire coils and continued by an upright arm extending through said eye of the adjacent tongue arranged adjacent to the neck in the associated band, and by a U-shaped wirebailhaving two limbs and a crosspiece, each of said two limbs extending toward the neck of one of said teeth through the eye of one of said palatal tongues arranged adjacent to the cutting edges of said teeth, and said crosspiece extending across the back of said teeth adjacent to the cutting edge thereof, each of said bands being adapted toapply itself snugly toone of said teeth at thefront and back thereof and at the side facing the other of said teeth when the labial tongues arranged adjacent to the cutting edges are thus pulled apart.

2. In a dental matrix comprising a pair of flexible bands having superposed side edges, each of said bands being formed at each end with a longitudinal slot not extending to the center of the length of the band to form two similarly shaped tongues above and below said slot, respectively, said bands being suitable for slidable insertion into a gap between two front teeth with a labial and a palatal tongue of each band arranged adjacent to the neck of said teeth and a labial and a palatal tongue of each band arranged adjacent to the cutting edge of said teeth, the improvement which resides in that each of said tongues is formed in its end with an eye, and that said bands are connected by two resilient wire bails which extend transversely to said tongue ends 4 arranged adjacent to the necks of said teeth, one of said bails extendin labially, the other palatally of said bands, each of said wire bails comprising a wire coil associated with each'of said hands, a wire limb branching obliquely from each of said wire coils and continued by an upright arm extending through said eye of the adjacent tongue arranged adjacent to the neck in the associated band, by a U-shaped wire bail having two limbs and a cross piece, each of said limbs extending toward the neck of one of said teeth through the eye of one of said palatal tongues arranged adjacent to the cutting edges of said teeth, and said crosspiece extendin across the back of said teeth adjacent to the cutting edge thereof, by a spring wire grip having a resilient circular portion and two jaws, each of which forms a neck part, a divergent arm, and an outwardly open hooked end, and a ferrule embracing said neck parts with a clearance between said neck parts in said ferrule, and by a wire eye associated with each of said labial tongues arranged adjacent to said cutting edge, each of said wire eyes comprising an inner side portion extending through the eye of the associated tongue and an outer side portion in engagement with said hooked end of one of said jaws, said bands, wire bail, jaws and ferrule being so related in size, shape, and resiliency that the grip is adapted to pull, through the intermediary of said wire eyes, said labial tongues arranged adjacent to the cuttin edge apart in mutually opposite directions when said jaws are allowed to bear with their neck parts outwardly against said ferrule and each of said bands being adapted to apply itself snugly to one of said teeth at the front and back thereof and at the side facing the other of said teeth when said labial tongues arranged adjacent to the cutting edges are thus pulled.

JULIUS WALSER.

References Cited in the file of this patent Y UNITED STATES PATENTS Number Name Date 701,799 Crenshaw June 3,1902 765,084 Knowles July 12, 1904 FOREIGN PATENTS Number Country Date 263,419 Switzerland Dec. 16, 1949 

